A two dimensional load distribution center position detection device which calculates the load acting on a sheet shaped sensor and the center position of the load is desired. Such a 2D load distribution center position detection device is applied for measuring the load and the barycentric position of the load of the bottom of a robot's feet by using the sensor covering the bottom of the feet. Or, such a 2D load distribution center position detection device is applied for measuring a load and the center position of the load acted on robot finger tips when the robot pinches an object by the finger tips covered by the sensor. Such a 2D load distribution center position detection device is desired to have a fine resolution in measuring a load and its central position, and the number of terminals of its sensor for outputting signals indicating the load and the central position is desired to be small. Furthermore, this sensor is desired to be easily manufactured and to cover variously shaped objects.
Japanese Patent Publication No. 1308321 discloses a detection method for surface pressure data, which easily allows detection of the summation of surface pressures and its barycentric position by using an extremely simple device. The detection method for surface pressure data is characterized by including steps of: using a pressure detector composed of a sheet resistance material in a first layer consisting of a flexible material with high conductivity, a pressure-sensitive plate in a second layer whose conductance approximately linearly varies due to an effect of pressure, and a sheet resistance material in a third layer with high conductivity; separately dividing a circumference in pressure detector into two pairs of opposite sides facing each other; applying electric voltages +a and −a to electrodes installed in a pair of opposite sides facing each other in the sheet resistance material in the first layer and to electrodes installed in another pair of opposite sides facing each other in the sheet resistance in the third layer via resistances respectively; and calculating a summation W of the surface pressure acting on the pressure detector based on the electric voltages and electric voltages VA and VB or VC and VD of a pair of electrodes in a first or second sheet resistance material by the following equation:W=k0(2a−VA−VB)=k0(2a+VC+VD)(K0 is a constant).
Japanese Patent Publication No. 1875498 discloses a method of positioning on a surface of an object by using a surface pressure sensor which is able to directly detect a position of a working end of an apparatus on the surface of the object by using a simple means, is adaptable for errors of relative position and direction between a positioning device and the object, and does not require processing for dead areas. The method of positioning on a surface of an object by using surface pressure sensor is characterized by, when positioning a working end of a device on a surface of the target object, including steps of: applying a flexible surface pressure sensor for simultaneously detecting a contact point and a contact force on an object; moving a contact point on the surface of the object to the working end by a drive device where its driving is controlled by a control instruction of a controller; comparing a contact position outputted from the surface pressure sensor according to a contact of the working end with a target position outputted from a target contact position setter which sets the target position in a position comparator and comparing a contact force outputted from the surface pressure sensor according to the contact of the working end with a target contact force outputted from a target contact force setter which sets the target contact force in a contact force comparator; inputting the comparison outputs of the position comparator and the contact force comparator as inputs of the controller to perform a control of the drive device for adjusting the position and the contact force of the contact point; and performing positioning of the contact point on the target position on the surface of the object at the target contact force.
Japanese Patent Publication No. 1928006 discloses a slip sensor having a simple configuration for detecting an existence of slip. The slip sensor is characterized by composing, between a pair of conductive sheets formed of a flexible material with high conductivity, a detector by holding an elastic insulator including many holes which make the sheets directly and partially face each other and by connecting electrodes installed on a pair of opposite sides in one conductive sheet and on another pair of opposite sides in the other conductive sheet with a variation detection circuit for detecting slip between a detector and an object based on a temporal variation of the barycentric position via a barycentric position detection circuit for obtaining the barycentric position of an electric current density between both of the conductive sheets.